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Topic: GFCI Question and Diagram Spot Check (Read 14550 times)

How reliable are GFCI outlets? I am planning on adding several receptacles and light fixtures to my basement (cinderblock walls, concrete floor). I've read several places, including some great wiring books, that GFCI's can be unreliable when used for appliances that are always on (such as freezers/fridges) or when multiple GFCI outlets share the same breaker. Others sound as if there is no reliability difference and not using GFCI's in a basement or workshop is akin to driving 200mph blindfolded on the highway while drunk. I do understand the logic for bathrooms and outdoor areas.

Here is my scenario. The receptacles will be used to power heating that is relatively low draw but is controlled by very precise proportional thermostats and is on 24/7. Additionally, the receptacles will be used to power professional grade incubators that need to be run continuously. So I can't afford the GFCI's to kill power because it can't handle normal fluctuation from running appliances on multiple receptacles. They are currently in a workshop with no issues on non-GFCI outlets but I need to move them down into the basement to free up my workshop. So in my situation, does using GFCI's pose a potential risk to cutting power to these appliances or is not using GFCI's a bigger risk?

Here is my proposed diagram for the wiring and receptacles. I'd appreciate hearing any any critiques on it if anyone has advice or a thumbs up? Again the receptacles will be running multiple thermostats 24/7 but will be a low power draw on each breaker. I may run a space heater in winter off the receptacle by the light switch.

FWIW, in CA: All kitchen receptacles are required to be GFIC. This includes your refrigerator, microwave, etc. All other outlets not found in a wet environment are required to be AFCI.

I'm not an electrician, nor do I play one on TV. I'm a project manager for an architectural firm and thus generally leave the more technical side of the electrical to the engineers and installing contractors.

Thanks but I'm more concerned with the reliability of GFCI's and their value in an environment where there's no open water sources. I have no problem installing them, even if useless, but not if that means risking losing power to the receptacles because they are unreliable for always on applications. This is what I'm trying to determine.

Some of the codes make a lot of sense. Others have nothing to do with safety (e.g., a receptacle must be provided for every parking spot in the garage).

Do you have a need for GFI outlets? Is your basement wet? If not you may not even need it.

My point above about the GFI outlets is they seem to work just fine for most kitchen appliances. So long as they don't fault to ground I cant see an issue.

Sometimes there can be a wet spot here and there on the basement floor after a heavy rain but nothing ever on the walls. There's no danger of flooding because I have a gravity fed drain that dumps out below grade.

I appreciate the help. The big difference with kitchen appliances is that they are only on for a limited time and at a constant power draw (as far as I know). I'm running multiple 'mini-appliances' that are always on and the thermostats are incredibly precise so fluctuate the power many times a second to maintain an exact temperature. A single night without power due to a flippped GFCI would be extremely bad for me so I'm trying to do my due diligence on them. I actually back up these precision thermostats with secondary back-up thermostats just in case the primary one fails at any given time.

I read that until recently the NEC guidelines gave a GCFI exemption for freezers/sump pumps/etc. in basements or garages because they performed so poorly. This is what gave me pause on using them.

d3nni5

You don't need them for EVERY receptacle either. One at the head of the series should do the trick for those downstream.

I run a pool pump 12+ hours a day on one. Never has tripped. My pool outlet is an outside receptacle in an all weather box, but not GFCI. The GCFI outlet is located "upstream" from that at the head of the circuit.

You don't need them for EVERY receptacle either. One at the head of the series should do the trick for those downstream.

I run a pool pump 12+ hours a day on one. Never has tripped. My pool outlet is an outside receptacle in an all weather box, but not GFCI. The GCFI outlet is located "upstream" from that at the head of the circuit.

Right, if I use them that was going to be the plan. They start to add up fast compared to standard receptacles. That's reassuring too about your pool pump, thanks.

I work in the electrical industry. That being said personally I wouldn't put them in. If you feel like you need to, they make an alarming GFCI that has an audible alarm that sounds when tripped. Might be worth the couple extra bucks it costs to know if/when it trips.

Right, if I use them that was going to be the plan. They start to add up fast compared to standard receptacles. That's reassuring too about your pool pump, thanks.

If you do that and something trips for whatever reason, you shut down that entire leg of your operation. If you're going to use GFCI's i think i'd use them on each receptacle and wire them so power goes through instead of getting shutting down the entire run of power. that way when one trips it only shuts down appliance causing the ground fault and your minimizing damage. Thats probably the best "best of both worlds" option for you. Or you install one at the head of each circuit like you were saying and do a few "dry runs to see if there are any obvious problems. If nothing shuts down at full load for a few days i think you'll be good. They can be problematic especially an outside circuit tied into one gfci in the garage which is how most guys around here wire them up. Think extension cords and wet grass. heh

I work in the electrical industry. That being said personally I wouldn't put them in. If you feel like you need to, they make an alarming GFCI that has an audible alarm that sounds when tripped. Might be worth the couple extra bucks it costs to know if/when it trips.

Thanks, the alarm is a great idea. I guess if do use them and they keep tripping, I can switch them out with regular receptacles.

If you do that and something trips for whatever reason, you shut down that entire leg of your operation. If you're going to use GFCI's i think i'd use them on each receptacle and wire them so power goes through instead of getting shutting down the entire run of power. that way when one trips it only shuts down appliance causing the ground fault and your minimizing damage. Thats probably the best "best of both worlds" option for you. Or you install one at the head of each circuit like you were saying and do a few "dry runs to see if there are any obvious problems. If nothing shuts down at full load for a few days i think you'll be good. They can be problematic especially an outside circuit tied into one gfci in the garage which is how most guys around here wire them up. Think extension cords and wet grass. heh

That's a good point. So no daisy chaining. So something like this should keep the other outlets working independently in the event that one trips?

Not an electrician, but I pretended like I knew what I was doing when finishing our basement. Actually I read a good bit too like it seems you're doing. I won't put one in for that scenario. The gfci is meant to respond quicker than your regular breaker. I'd just rely on that for what you're doing. Just one amatuers opinion.

Thanks, the alarm is a great idea. I guess if do use them and they keep tripping, I can switch them out with regular receptacles.

That's a good point. So no daisy chaining. So something like this should keep the other outlets working independently in the event that one trips?

the last GFCI i wired up had a tab on the back for pass through power in the event of a trip and a tab for tripping the gfci and the rest of the circuit. when you go shopping look at the box. it should have details for this. So you shouldnt need all those jumpers and wirenuts like your diagram. but yeah, you've got the idea.

Electrician here, depending on where you are it's required to have GFCI's in basement...so depends on your situation and if you like to keep things up to code etc. Personally in all my 17+ years I've only had a few fail where they need to be replaced and I would say 90% of those were in outside damp locations.

BTW there are several versions of even basic GFCI, those for use in wet environments such as outdoors or high humidity areas think greenhouse etc. And the rest are the basic NON WET locations GFCI, also as mentioned AFCI. Also there is GFCI and AFCI breakers, so that would protect the whole circuit and sometimes can be cheaper depending on the brand and style of panel you got.

I've never heard of any issues of GFCI getting tripped intermittently from equipment (that the equipment wasn't faulty) and have worked with many BIO LABS over the years, using all sorts of equipment, most of these are new TI's....(Tenant Improvements) so they require to be up to the most recent codes so most have GFCI or equivalent protection on the circuits.

With that said, if your worried about getting shocked or need the nanny state code for your business then put in the GFCI's.

Instead I would just buy the most expensive Heavy Duty receptacles you can get. It's worth the extra $1 for the heavy duty ones, it should require some force to insert and remove the plug IMO. Whenever I do any install or replace and outlet I use the HD outlets, this is important for heavy draw devices like heaters, refrigerators/freezers & coffee makers.

You would be surprised to see how loose the wires and connections are on Kitchen outlets, the reason why most electrical fires start in the kitchen or garage is due to contractor grade outlets (cheapest) and nobody ever re-tightens connections and use of heavy draw appliances/tools that heat up the wire and loosen it over time....

sorry for my rant...one of my issues I think that needs to be addressed.

Thanks everyone for the input. It sounds as if I'd be fine without using GFCI's so will probably go that route. I thought so but it's good to hear some unbiased feedback. The new panel is going in next week and then I get to start.

Instead I would just buy the most expensive Heavy Duty receptacles you can get. It's worth the extra $1 for the heavy duty ones, it should require some force to insert and remove the plug IMO. Whenever I do any install or replace and outlet I use the HD outlets, this is important for heavy draw devices like heaters, refrigerators/freezers & coffee makers.

Agree and definitely want to use good quality parts for this. I was planning on using the Leviton 5352 outlets.

It doesn't seem like you need another 2 cents but I will toss in anyway just fyiI use portable gfi protection at work due to osha requirement and just good practice when using hand tools. I've had tripping problems when I have used 2 inline to get more 3 way outlets. The electrons get mixed up easier and flip out always at the worst time. It always causes an unwanted hike back to the device and sometimes in a dark room. I have not seen them installed on too many lighting circuits btw. They do not install them on sump pumps, not sure if it is just because it is a critical device or because inductive loads (motors) false trip more often.They also take up room in your outlet boxes making you step up to a 4 square especially when your running 12awg. You may want to get 4 squares with the single gang adapter plate just to have plenty of room for the normal outlets. Cramming the gfis into a single gang has probably caused fires somewhere. I would probably put one in just for running tools off of and leave the rest normal. It's interesting to see all the ways they can be wired wrong too, I recently purchased a fixerupper and when I flip the fan and light on in the master bathroom the gfi in the 2nd bathroom trips, killing the light in the second bathroom. I will be rewiring soon and am doing mental schematics of wonder.Also a bit of useful trivia to contemplate: a gfi only monitors the current to verify that the same amount goes out on the black lead and returns on the white, it won't open the circuit if you find yourself frying in the middle of the 2 leads until you ground yourself or one of the leads and unbalance the line. Hopefully interesting at least, good luck with your project.

I've had much better luck with GFCI breakers (or GFCI/AFCI breakers) than outlets. It seems the outlets are never robust enough for the outside or garage environment and they fail after a while. Plus, in the last few years with trip free GFCI outlets the breakers are not that much more expensive than the outlet.

This is just my FWI input.If the floor is bare concrete and the outlet is what the the code would call a "convenience receptacle" it needs to be gfci'd.Concrete even when dry is a good conductor of electricity.If the floor is finished its not necessary.If the outlet is for a dedicated item "the sump pump" no gfci is required. (some states do require it) But it should be a single outlet only. I would never do that for anything that needs to stay on. sump pump, sewage pump, water heaters with the draft fan (usually just plug in not hard wired) fridge, freezer etc.No gfci is required for 240 volt outlets. Like shop tools. Exception being pools and spas.Outlets on the ceiling (garage door opener) no not need gfci. (not considered a convenience receptacle)You can not install a gfci down the line from a gfci that is already protecting that line. They will trip each other.

It doesn't seem like you need another 2 cents but I will toss in anyway just fyiI use portable gfi protection at work due to osha requirement and just good practice when using hand tools. I've had tripping problems when I have used 2 inline to get more 3 way outlets. The electrons get mixed up easier and flip out always at the worst time. It always causes an unwanted hike back to the device and sometimes in a dark room. I have not seen them installed on too many lighting circuits btw. They do not install them on sump pumps, not sure if it is just because it is a critical device or because inductive loads (motors) false trip more often.They also take up room in your outlet boxes making you step up to a 4 square especially when your running 12awg. You may want to get 4 squares with the single gang adapter plate just to have plenty of room for the normal outlets. Cramming the gfis into a single gang has probably caused fires somewhere. I would probably put one in just for running tools off of and leave the rest normal. It's interesting to see all the ways they can be wired wrong too, I recently purchased a fixerupper and when I flip the fan and light on in the master bathroom the gfi in the 2nd bathroom trips, killing the light in the second bathroom. I will be rewiring soon and am doing mental schematics of wonder.Also a bit of useful trivia to contemplate: a gfi only monitors the current to verify that the same amount goes out on the black lead and returns on the white, it won't open the circuit if you find yourself frying in the middle of the 2 leads until you ground yourself or one of the leads and unbalance the line. Hopefully interesting at least, good luck with your project.

Thanks for the input. I appreciate hearing everyone's 2 cents. I am planning on using a 2 gang box and either using the adapter or maybe adding a second outlet and reducing the total number of boxes. After running the box fill calculations, I don't see how 12 gauge can fit in a single gang box that's a middle of the run outlet.

I've had much better luck with GFCI breakers (or GFCI/AFCI breakers) than outlets. It seems the outlets are never robust enough for the outside or garage environment and they fail after a while. Plus, in the last few years with trip free GFCI outlets the breakers are not that much more expensive than the outlet.

Thanks, the breakers have come down a bit but I think I'm going to steer clear of using GFCI for the outlets that are in dedicated use.

This is just my FWI input.If the floor is bare concrete and the outlet is what the the code would call a "convenience receptacle" it needs to be gfci'd.Concrete even when dry is a good conductor of electricity.If the floor is finished its not necessary.If the outlet is for a dedicated item "the sump pump" no gfci is required. (some states do require it) But it should be a single outlet only. I would never do that for anything that needs to stay on. sump pump, sewage pump, water heaters with the draft fan (usually just plug in not hard wired) fridge, freezer etc.No gfci is required for 240 volt outlets. Like shop tools. Exception being pools and spas.Outlets on the ceiling (garage door opener) no not need gfci. (not considered a convenience receptacle)You can not install a gfci down the line from a gfci that is already protecting that line. They will trip each other.

Thanks for the info. I didn't realize concrete was a good conductor and had thought it was more geared towards moisture. I don't think there'll ever be a problem but it probably couldn't hurt to put down some rubber matting until I can finish the floor.

Not an electrician, but very familiar with electricity.IMHO GFCI are worthless. I have one that trips occasionally even when not in use in my kitchen. GFCI receptacles are supposed to be replaced after the first time they trip. I mean get real, one and done ? I personally think it's a scam to make you pay more for plug-ins more often.Unless stupid building code requires it, I wouldn't bother. Just make sure your plugs and wiring/cords are in good shape.

Not an electrician, but very familiar with electricity.IMHO GFCI are worthless. I have one that trips occasionally even when not in use in my kitchen. GFCI receptacles are supposed to be replaced after the first time they trip. I mean get real, one and done ? I personally think it's a scam to make you pay more for plug-ins more often.Unless stupid building code requires it, I wouldn't bother. Just make sure your plugs and wiring/cords are in good shape.

Thanks for the input. I've read similar sentiments about the GFCI's being required in clearly non-aquatic environments for financial, not safety, reasons.

On a separate but similar note, some contractors are ripping up the kitchen floor today to replace some massive termite damage. They discovered one kitchen outlet had been wired into the stove . I had no idea this had been done... 14 gauge on a 50 or 60 amp breaker. It's cut and capped now. I'll be using a GFCI for this one though when I decide how I want to rewire.

I just wanted to thank everyone again for their help and advice with this thread. I got my new panel in Monday with plenty of open spots so I can finally start. This weekend will be spent learning to bend EMT offset and mounting all the boxes/conduit. It feels good learning a new skillset like this. I picked up 500' rolls so now I'll need to find some more projects to use the extra 400' or so on.

So I learned how to bend EMT off-set and got the first set of boxes installed with conduit run. I'm running into a problem with installing the outlets though. The metal tabs on the outlets are preventing a flush fit with the single outlet covers for 4'' square boxes (images below). This is not a problem in the single gang boxes.

Is this just a really simple solution of bending the metal tabs inside the box? I'm not really clear on what the purpose of these tabs are so didn't want to bend them without checking.